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Remembering our past: Functional neuroanatomy of recollection of recent and very remote personal events. Cerebral Cortex, in press

Rotman Research Institute, Baycrest Centre for Geriatric Care, 3560 Bathurst St., Toronto, Ontario, M6A 2E1, Canada.
Cerebral Cortex (Impact Factor: 8.67). 12/2004; 14(11):1214-25. DOI: 10.1093/cercor/bhh082
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ABSTRACT Functional magnetic resonance imaging was used to study brain regions implicated in retrieval of memories that are decades old. To probe autobiographical memory, family photographs were selected by confederates without the participant's involvement, thereby eliminating many of the variables that potentially confounded previous neuroimaging studies. We found that context-rich memories were associated with activity in lingual and precuneus gyri independently of their age. By contrast, retrosplenial cortex was more active for recent events regardless of memory vividness. Hippocampal activation was related to the richness of re-experiencing (vividness) rather than the age of the memory per se. Remote memories were associated with distributed activation along the rostrocaudal axis of the hippocampus whereas activation associated with recent memories was clustered in the anterior portion. This may explain why circumscribed lesions to the hippocampus disproportionately affect recent memories. These findings are incompatible with theories of long-term memory consolidation, and are more easily accommodated by multiple-trace theory, which posits that detailed memories are always dependent on the hippocampus.

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Available from: Morris Moscovitch, Jul 06, 2014
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    • "Other regions identified in this analysis are associated with processes that are also likely to be involved in generating dialogic scenarios. For example, right MTG has been associated with accurate and confident recall (Chua et al., 2006, Giovanello et al., 2010), while the right precuneus has been associated with retrieval of verbal episodic memory (Fernandes et al., 2005), context-rich autobiographical memories (Gilboa et al., 2004) and first-person perspectives memories (sometimes called 'field' memories; Nigro and Neisser, 1983; Eich et al., 2009). The activation of cingulate gyrus for vividness ratings, though likely not specific to this process, has been linked previously to a right anterior insula network involved in affective engagement (Touroutoglou et al., 2012). "
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    • "For example, reports of autobiographical memories by patients with mTLE have a paucity of perceptual features (St- Laurent et al., 2009). In healthy individuals, hippocampal activation has been shown to correlate with ratings of vividness (Gilboa et al., 2004; Rabin et al., 2010), imagery use (Andrews-Hanna et al., 2010) and intensity of reliving (St Jacques et al., 2012; but see Daselaar et al., 2008) during the retrieval of autobiographical events. Furthermore, evidence from functional neuroimaging indicates that connectivity between the hippocampus and posterior visual association regions supports retrieval and elaboration of episodic details during autobiographical recall (McCormick et al., in press). "
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    • "Thus, the hippocampus respected the distinction between the recent and remote memories. Functional differentiation down the long axis of the hippocampus has been documented in a range of species including humans (e.g., Moser and Moser, 1998; Maguire et al., 2000; Gilboa et al., 2004; Rekkas and Constable, 2005; Fanselow and Dong, 2010; Poppenk and Moscovitch, 2011; Ranganath and Ritchey, 2012; for a recent review see Poppenk et al., 2013). Bonnici et al.'s (2012a) findings clearly prompt further questions about what might be occurring within anterior and posterior hippocampus during autobiographical memory recall. "
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